路外停车右转驶入对主路上游车流影响的动态长度模型

A Model for Describing Dynamic Influence Length of Upstream Following Vehicles on Main Road when Front Vehicles Turning Right and Entering into Off-street Parking Lot

以城市路外停车出入口影响区作为研究对象，将拟停放车辆从最右侧车道右转驶离主路进入停车场的过程对于上游运行车辆的影响区长度表述为停放车辆减速进入停车场距离和跟驰运行车辆的交通波传播距离2个部分。通过理论分析并结合调查数据建立了基于不同驶入时间及不同饱和度下影响区动态长度的计算模型，确定了停车影响时间、速度变化系数等主要参数的适用条件。通过实例并采用VISSIM5．3软件对模型进行了仿真对比验证，主要结论有：（1）当驶入时间在4～8S时，饱和度与影响区长度呈现反比关系；驶入时间大于8s时，饱和度与影响区长度呈现正比关系；（2）当饱和度在[0．46～0．5]驶入时间在4～15s时车辆驶入对主路上游车辆没有影响；（3）当饱和度大于0．6，驶入时间大于9s时，车辆驶入对主路上游车辆的影响长度增幅明显。

Taking the influence area of the access of off-street parking lot in a city as the research object , when the parking car turns right from the rightest lane of the main road into the access, the vehicles which are the upstream of the access to the main road are affected, and the influence length is presented as 2 parts, one is the deceleration distance of the parking car and the other is the propagation distance of traffic wave caused by the following vehicles. By the way of theoretical analysis and field investigation data, we presented a model that represents the dynamic influence length under the condition of different entering time and saturation. The applying conditions of the main parameters such as park influence time and variation coefficient of speed are confirmed. By contrasting the simulation of VISSIM 5.3 and the model, it is concluded that （ 1 ） when the entering time is between 4 s and 8 s, the saturation and the influence length are in inverse proportion, while the entering time is more than 8 s, the saturation and the influence length are in direct proportion ; （2） when the saturation is between 0. 46 and 0.5 and the entering time is between 4 s and 15 s, the parking car has no effect on the vehicles; （3） when the saturation is more than 0.6 and the entering time is more than 9 s, the effect of parking car on the vehicles influential length increased significantly.